Before creating a disk group, consider the following:

• The type of volume configurations that are required.

• The number of LUNs required for the disk group.

• The implications of backup and restore operations on the disk group setup.

• The size of databases and logs which depend on the traffic load.

• The number of disk groups and volumes that are needed for Exchange. Typically an SFW disk group corresponds to an Exchange storage group, with a separate volume for each database and for the transaction log.

• For campus clusters, consider the following:

  • The disk groups and number of disks on each site

    For campus clusters, each disk group must contain an equal number of disks on each site.

  • Each volume should be a mirrored volume with one plex of the volume on Site A's storage array and the other plex of the volume on Site B's storage array.

• In a Microsoft cluster, plan to include a disk group for the mirrored quorum resource. If possible, use small disks. Microsoft recommends 500 MB for the quorum disk. The number of disks recommended are as follows:

  • In a high-availability configuration, Veritas recommends using at least 3 disks for the mirrored quorum resource.

  • In a campus cluster configuration, because each site must contain an equal number of disks, Veritas recommends a 4-way mirrored quorum, 2 mirrors on each site.

The following topics provide additional guidelines for specific configurations: